feat: admin can change user display name

API: new updateName adminProcedure in user router
- Input: userId + name (min 1, max 200 chars)
- Argon2 not involved (name only, not password)
- Audit log: "Changed name from X to Y"

UI: "Display Name" editable section in user edit modal
- Shows current name with "Edit" link
- Click Edit: inline input with Save/Cancel + Enter/Escape
- Auto-focuses input, saves on Enter
- Invalidates user list on success

Co-Authored-By: claude-flow <ruv@ruv.net>

packages/api/src/router/user.ts

@@ -196,6 +196,41 @@ export const userRouter = createTRPCRouter({
       return updated;
     }),
 
+  updateName: adminProcedure
+    .input(
+      z.object({
+        id: z.string(),
+        name: z.string().min(1, "Name is required").max(200),
+      }),
+    )
+    .mutation(async ({ ctx, input }) => {
+      const before = await ctx.db.user.findUniqueOrThrow({
+        where: { id: input.id },
+        select: { id: true, name: true, email: true },
+      });
+
+      const updated = await ctx.db.user.update({
+        where: { id: input.id },
+        data: { name: input.name },
+        select: { id: true, name: true, email: true },
+      });
+
+      void createAuditEntry({
+        db: ctx.db,
+        entityType: "User",
+        entityId: updated.id,
+        entityName: `${updated.name} (${updated.email})`,
+        action: "UPDATE",
+        ...(ctx.dbUser?.id ? { userId: ctx.dbUser.id } : {}),
+        before: before as unknown as Record<string, unknown>,
+        after: updated as unknown as Record<string, unknown>,
+        source: "ui",
+        summary: `Changed name from "${before.name}" to "${updated.name}"`,
+      });
+
+      return updated;
+    }),
+
   // ─── Resource Linking ──────────────────────────────────────────────────
 
   linkResource: adminProcedure